Hoisting apparatus.



No. 759,201, PATENTED MAY 3, 190'4.

H. 1). STRATTON.

.HO'ISTING APPARATUS. APPLICATION FILED DOT. 17, 1903- NO MODEL. 2SHEETS-SEEET 1.

. SUM/mugs No. 759,201. PATEN'TED MAY 3, 1904.

H. D. STRATTON. HOISTING APPARATUS.

APPLICATION FILED OUT. 17, 1903.

. H0 MODEL. 2 SHEETS-SHEET 2.

cl. u .n a 9 UNITED STATES Patented May 3, 1904.

PATENT OFFICE.

HARRISON D. STRATTON, OF PHILADELPHIA, PENNSYLVANIA.

HOISTING APPARATUS.

SPECIFICATION forming part of Letters Patent N0. 759,201, dated May 3,1904.

Application filed October 17, 1903.

To all whom it may concern:

Be it known that I, HARRISON D. STRATTON, a citizen of the UnitedStates, residing at Philadelphia, in the county of Philadelphia andState of Pennsylvania, have invented a new and useful Improvement inHoist-ing Apparatus, of which the following is a specification.

My invention relates to electric hoisting apparatus, such as is used forraising coal, stone, and the like.

It consists of means for preventing the energizing of the motor withoutfirst releasing the brake from the moving portion of the device and ofsynchronous means for cutting off the current from the motor andapplying the brake.

It further consists of a safety-stop for automatically cutting off thecurrent from the motor by the action of the hoisted article.

It further consists of other novel features of construction, all as willbe hereinafter fully set forth.

Figure 1 is a side elevation of a hoisting-machine embodying myinvention. Fig. 2 is a top plan thereof. Figs. 3, 4, 5, and 6 show indifferent positions the rheostat and the brake-detent. Fig. 7 shows thesafety-stop portion of the device.

Similar numerals of reference indicate corresponding parts in thefigures.

Referring to the drawings, 1 designates a track which is traversed by myautomatic device when it is used for carrying as well as hoisting coal,stone, or the like.

2 designates the frame of the device,on which is mounted a motor 3,connected by suitable gearing 4, 5, and 6 to a drum 7, on which is wounda cable 8 or the like, to which is attached a bucket 9 or other articleto be hoisted. Mounted on the frame 2 is a switch or rheostat 10, to thelever 11 of which is at-. tached a segmental cam-plate 12, having aflattened side 13.

On the arbor 14 of the motor or at any other convenient point on theshafting is "mounted a brake 15, from which a rod 16 leads to alever 17.The brake is held in normal engagement on the arbor 14 by means of alever 18, pivoted at 19 on a bracket 20, attached to the frame 2. Thelever 18 carries an idler Serial No. 177,421. (No mcdel.)

21, hearing against the lever 17 and is actuated by a spring 22. I haveshown the brake 15 as formed oftwo segments of an annulus Withprojecting ends. These may advantageously be separated whenbrake-pressure is removed by a spring 155, adjustably connected to oneof the ends and bearing against the other, as shown in Fig. 1.

Secured to the bracket 20 is a pivoted lever 24, having a lug normallylying in the path of the lever 17. The head 26 of the lever 24 bearsagainst the periphery of the cam 12.

Suspended on a suitable bracket below the frame 2 is a cut-out or safetyswitch 27, interposed in the line 28, which connects the rheostat 10 andmotor 3. A dog 29 is supported beneath the frame 2 in the upward path ofthe bucket 9 or other article to be hoisted. By means of a bell-cranklever 30 and bolt 31 the dog 29 is operatively connected to open thecut-out switch 27 when moved upwardly.

The operation is as follows: Assuming that the device is at rest, theparts will stand in the position shown in Figs. 4 and 5 of the drawings,in which the rheostat 10 is opened, so as to cut off the current from adynamo (not shown) to the motor 3 and in which the lug 25 has beenwithdrawn from the path of the brake lever 17, which has therefore beenmoved by the action of the lever 18, actuated by its spring 22, so as tobring the brake 15 to bear against the arbor 14 on the motor 3. To startthe machine, it is of course necessary to turn the rheostat-handle 11,which in turn rotates the cam 12. This cannot, however, be done untilthe brake-lever 17 has been moved to the position shown in Figs. 1, 3,and 6, so that the lug 25 may engage therewith. When the brake-lever 17has been moved to its inoperative position, as shown in Figs. 1, 3, and6, the mere turning of the cam 12 through the handle 11 acts directly toforce the lug 25 into its operative engagement with the brakelever. Tostop the machine, it is necessary to open the rheostat by rotating thehandle 11 to the position shown in Figs. 4 and 5 of the drawings, wherethe flat face 13 of the cam 12 is adjacent the bracket 4. This permitsthe head 26 to move outward, as shown in Figs. 4 and 5, so that thespring 24 removes the ing 25 out of the path of the brake-lever 17. Thebrake 15 is then automatically forced against the arbor 1 1 by theaction of the spring 22 and lever 18 acting on the brake-handle 17.

It will be understood that the rheostat or controller 10 is adapted tooperate the motor 3 in either direction and that the circular portion ofthe periphery of the cam 12 engages with the head 26 whether the bucketis being hoisted or lowered.

The brake-lever 17 is shown in Fig. 1 as provided with a handleextending below the bracket 20, so that in case of failure of the spring22 or lever 18 the brake may be operated by hand in the ordinary manner.

It will be seen that it is impossible to start the machine withoutreleasing the brake and that it is equally impossible to stop themachine without automatically throwing the brake into operation.

As an additional safeguard against the carelessness of the operator 1have provided the device shown in Figs. 1 and 7 of the drawings, wherethe dog 29 is interposed in the upward path of the bucket 9 when it israised beyond its proper height. It will be seen by reference to Fig. 7that when the edge of the bucket 9 strikes the dog 29 the switch 27 willbe opened and the current cut off from the motor. It is evident thatthis prevents the bucket being drawn up against the drum 7.

If preferred, the block 9 or a hoistinghook may be made to strike thedog 29 with the same effect. It will also be seen that the spring 32 bywhich the lever 30 is actuated is so positioned as to rapidly increasethe throw of the bolt 31, whereby the switch 27 is opened withoutsparking.

It is evident that various changes may be made by those skilled in theart which will come within the scope of my invention, and 1 do not,therefore, desire to be limited in every instance to the exactconstruction herein shown and described.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is

1. An electric hoist comprising a motor, a drum operatively connected tosaid motor, a switch, a brake, mechanically-actuated means for forcingsaid brakeinto its operative position, means for preventing theoperation of said brake-forcing means and means connected with saidswitch for holding said preventing means in operative position.

2. An electric hoist comprising a motor, a drum operatively connected tosaid motor, a switch, a brake, mechanically-actuated means for forcingsaid brake into its operative position and means interposed between saidbrake and said switch for preventing the openingof said switch when saidbrake is in its operative position.

3. An electric hoist comprising a motor, a drum operatively connected tosaid motor, a switch, a brake, mechanically-actuated means for forcingsaid brake into its operative position and means interposed between saidswitch and said brake and operative alternatively to prevent the closingof said switch while said brake is in its operative position and torelease said brake-foreing means when said switch is opened.

1. An electric hoist comprising a motor, a

drum operatively connected to said motor, a switch, a cam on saidswitch, a spring-actuated brake and means engaging with said cam forpreventing the closing of said switch while said brake is in itsoperative position.

5. An electric hoist comprising a motor, a drum operatively connected tosaid motor, a switch, a cam on said switch, a spring-actuated brake andmeans engaging with said cam for holding said brake out of its operativeposition when said switch is closed.

6. An electric hoist comprising a motor, a drum operatively connected tosaid motor, a switch, a cam on said switch, a spri1'1g-actu ated brake,a lever connected to said brake, a lug inter iiosable in the path ofsaid lever and means connected with saidlug and cngageable with said.cam whereby the opening of said switch acts to bring said brake to itsoperative position.

7. In an electric hoist, a motor, a drum, a brake, automaticallyoperated, mechanical means for forcing said brake into operativeposition and alternatively manual means for operating said brake.

HARRISON D. STRAT ON.

\Vitnesses:

\V. S. \VAnn, (Jrno. L. Ooornn.

